The BBC Radio Ulster presenter Stephen Clements has died suddenly. He was 47.
The broadcaster had presented the mid-morning Stephen Clements Show on the station since September.
In a statement, Stephen's brother Gavin Clements said: "We are devastated to lose Stephen who was deeply loved by his family and friends.
"We would ask for time to come to terms with this news and for privacy at this difficult time."
The presenter, who was married with two children, began his radio career with Citybeat.
He then hosted Q Radio's Breakfast Show for seven years, before moving to the BBC last year.
Before working in radio, Mr Clements studied geography at university and lived in South Korea for a period teaching English.
BBC Northern Ireland Director Peter Johnston said: "We are sorry to bring you the sad news of the passing of our colleague Stephen Clements.
"Our thoughts are with Stephen's family, friends and colleagues, at this difficult time."
Friends and colleagues have been quick to pay their respects to Mr Clements, who began his full-time career as a radio presenter in his late thirties and quickly became highly popular.
Writing on Twitter, TV presenter Eamonn Holmes sent his "heartfelt condolences" to the Clements family.
No more chats @radiostephen .... I'll miss you , your listeners will miss you. My Heartfelt condolences to your family. A lesson for us all to live life because we don't know how long it will last. Sad , sad times. How can you be gone ? #RIP— Eamonn Holmes (@EamonnHolmes) January 7, 2020
Fellow BBC Radio Ulster presenter Stephen Nolan said his colleague's "warmth on air was a true reflection of the real you - a kind, decent human being with so much natural talent".
Stephen - your warmth on air was a true reflection of the real you - a kind, decent human being with so much natural talent.— Stephen Nolan (@StephenNolan) January 7, 2020
My heartfelt condolences to your family.
We will miss you.
Mr Clements was patron of the charity Autism NI, which was among those to post online tributes.
Autism NI are saddened to hear the sad passing of our Patron Stephen Clements. Our thoughts and prayers are with his immediate family and friends. Stephen was a great supporter for autism across Northern Ireland. pic.twitter.com/pwCC4lTlAX— Autism NI (@AutismNIPAPA) January 7, 2020
The Mary Peters Trust also paid tribute to Mr Clements.
We are so sad to hear about the loss of Stephen Clements who was a great supporter of the Trust. Love and thoughts with his family.— Mary Peters Trust (@MaryPetersTrust) January 7, 2020
Politicians have remembered Mr Clements as "a true gentleman" and "incredible talent".
Absolutely devastating news. Have been a fan since Q days. We were in touch over Christmas & New Year. An incredible talent who was always willing to help others. Please keep his wife, little children and wider family in your prayers. https://t.co/oJ16TD3Qe3— Arlene Foster (@DUPleader) January 7, 2020
I am deeply saddened to hear of the passing of Stephen Clements— Michelle O’Neill (@moneillsf) January 7, 2020
His radio shows on BBC Radio Ulster & Q Radio brought his legion of listeners joy through his music & humour
I would like to extend my condolences to his wife, children, family & colleagues at this very sad time
So so saddened to hear of the passing of Stephen Clements. A true gentleman and incredibly talented broadcaster. A tragic loss 😢— Paula Bradshaw MLA (@PaulaJaneB) January 7, 2020
Many tributes have also been paid by members of the public, who have expressed shock at the news of Mr Clements' death.
Stephen Clements was unique. You felt he cared about his listeners individually, you knew he made a difference to their day, and he knew the importance of humour and the 'small stuff' as a balance to the 'big stuff'. RIP you utter star. @radiostephen @bbcradioulster @goQradio— Anthea Irwin (@AntheaIrwin) January 7, 2020
The Q Radio breakfast show became one of the most-listened to radio programmes in Northern Ireland during his time there.
In June 2019, Mr Clements announced that he was leaving the station to join BBC Northern Ireland.
He subsequently co-presented the BBC NI TV series Open for Summer during the Open Golf Championship in Portrush in 2019.
He also co-hosted BBC Northern Ireland's Children in Need programme in November 2019 with Holly Hamilton.
Mr Clements took over Radio Ulster's mid-morning programme from veteran presenter Sean Coyle in September 2019, saying it had always been his "dream" to work for the BBC.
He is survived by his wife and two children.